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Discussion on SH7018

The construction in the picture is not part of a railway track, although the steels may once have come from railway stock. It was a bridge to the reservoir water outlet pier. A submerged brass stopcock reached from the pier opens the water supply to the hydroelectric engine shed further downstream near Penmaenuchaf.

The hydroelectric system at Penmaenuchaf was built in Edwardian times and is now obsolete. (Google: "Penmaenuchaf History")